The invention relates to an anti-friction bearing for linear movements comprising a bearing body which is guided movable on a rail in a longitudinal direction thereof, the bearing body having legs accommodating at least one part of the rail between them and a web connecting these legs integrally together, at least one rolling body cycle being allocated to each of the legs and each of the rolling body cycles having one load-transmitting rolling body row in engagement with one load-receiving running path of the respective leg and with one running path at one side face of the rail said side face being adjacent to said leg, the load-transmitting rolling body rows being preloadable between the respective allocated running paths and this preload being adjustable by preloading means.